Kinetic cavity preparation is a kind of cavity preparation method using a high-speed stream of carried aluminium oxide particles propelled by air pressure. We carried out cavity preparation on extracted primary and permanent teeth using the air-powder abrasive system KCP-2001J and observed the cavity through a dissecting mycroscope and SEM. The effects of cavity preparation using airentrained aluminium oxide kinetic instrumentation were compared with using high-speed rotary instrumentation.
The following conclusions were obtained.
1. The kinetic method of tooth preparation produced a smooth, clean preparation with a slightly rounded cavorsurface margin and a smooth cavity wall, without a distinct line-angle on the cavity wall to the cavity floor. No smear layer was observed.
2. Because of the above characteristics of the cavity form prepared by the airabrasive technique, advantages emerge for bonded restoration with composite resin material.
3. The nozzle of the air-abrasive instrument does not come into actual contact with the tooth, providing no tactile guidance. Skill is therefore necessary for free hand movement of the handpiece.
4. The air-powder stream cut even healthy enamel around the cavity. A preventive method is necessary for the protection of the enamel surface around the cavity.
5. No operative pressure, no vibration, very littleaudible sound, no cutting smell and high cutting speed during the air-abrasive treatment, all eliminate the tension on the part of the patient. Based on the above advantages kinetic energy instrumentation, can be considered as a suitable clinical procedure especially for Pediatric Dentistry.